ABSTRACT
Background The lifestyles of children and adolescents have changed extensively during the COVID-19 pandemic due to school suspension and social distancing measures, which can affect their sleep health. Existing studies have used convenient samples and focused on the initial months of the pandemic. Method As part of a territory-wide epidemiological study in Hong Kong, this cross-sectional study recruited primary and secondary school students by stratified random sampling. We investigated the pandemic's effects on sleep parameters using multivariate regression, adjusting for age, sex, household income, seasonality and presence of mental disorders, and the moderators and mediators of the effects. Findings Between 1 September 2019 and 2 June 2021, 791 primary and 442 secondary school students were recruited and analysed. Assessment during COVID predicted a longer sleep latency in both groups on school days (95% CI= 1.0-5.2 minutes, adjusted p-value= 0.010; and 95% CI= 3.9-13.0 minutes, adjusted p-value= 0.004, respectively) and non-school days (95% CI= 1.7-7.2 minutes, adjusted p-value= 0.005; 95% CI= 3.4-13.7 minutes, adjusted p-value= 0.014, respectively). Low household income was a moderator for later bedtime (adjusted p-value= 0.032) and later sleep onset (adjusted p-value= 0.043) during non-school days among secondary school students. Sex and digital leisure time were respectively not a moderator and mediator of the pandemic's effect on sleep parameters. Interpretation Changes associated with COVID have a widespread and enduring effect on the sleep health of school-aged students in Hong Kong. Household income plays a role in adolescent sleep health resilience, and effects of anti-epidemic measures on the health gaps of the youth should be considered. Funding Government of the Hong Kong Special Administrative Region, Food and Health Bureau, Health and Medical Research Fund (Ref. No.: MHS-P1(Part 1)-CUHK).